BREAKING The most devastating news. Louis Tomlinson's sister Félicité - a social media influencer - has been found dead at her home in London after a suspected heart attack. She was just 18-years-old https://t.co/3qGLRgbzx6pic.twitter.com/1Pdk2CYbs6

The Metropolitan Police Service told E! News that when emergency responders arrived, they found a female in cardiac arrest who was pronounced dead at the scene.

"Police are in the process of informing her next of kin," E! reported, according to a police statement. "At this stage the death is being treated as unexplained. A post-mortem examination will take place in due course."

The loss of Félicité Tomlinson comes just two years after the family lost their mother, who died from leukemia.